IDirectDrawSurface5::PageUnlock

This method unlocks a system-memory surface, allowing it to be paged out.

HRESULT PageUnlock(
  DWORD dwFlags
); 

Parameters

  • dwFlags
    This parameter is currently not used and must be set to zero.

Return Values

If the method succeeds, the return value is DD_OK.

If the method fails, the return value may be one of the following error values:

DDERR_CANTPAGEUNLOCK
DDERR_INVALIDOBJECT
DDERR_INVALIDPARAMS
DDERR_NOTPAGELOCKED
DDERR_SURFACELOST

Remarks

A lock count is maintained for each surface and is incremented each time IDirectDrawSurface5::PageLock is called for that surface. The count is decremented when IDirectDrawSurface5::PageUnlock is called. When the count reaches zero, the memory is unlocked and can then be paged by the operating system.

This method works only on system-memory surfaces; it will not page unlock a display-memory surface or an emulated primary surface. If an application calls this method on a display-memory surface, this method will do nothing except return DD_OK.

This method was not implemented in the IDirectDraw interface; it has no effect in Windows CE.

Requirements

OS Versions: Windows CE 2.12 and later. Version 2.12 requires DXPAK 1.0 or later.
Header: Ddraw.h.
Link Library: Ddraw.lib.

See Also

IDirectDrawSurface5::PageLock

 Last updated on Thursday, April 08, 2004

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